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Full text of "The Morphology And Evolution Of The Apes And Man"

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30            ilOBPHOLOGY AND EVOLUTION               ,
The bony palate differs from that in the Lemurs, and the foramen magnum is nearer to it than in them.
Of the foramina in the skull those for the olfactory nerves deserve special mention. In all Primates except litmus the olfactory filaments pass through the foramina in the cribriform plate of the ethmoid bone. In Tarsius there is no plate, and the olfactory nerve on each side passes through a single foramen as in Birds and in the Platypus (Orn ithorhyncli us).
Teeth.—The upper central incisors are not separated as in Lemurs; they are long and pointed, and they are much larger than the upper lateral incisors. The lower incisors constitute a pair of small cones (fig. 11). The upper canine teeth are smaller than the lower canines. The upper and lower molars are tricuspid, but the latter have an additional heel posteriorly. The dental formula isl JCJPaif Mf.
The sutures disappear earlier than in the Lemurs.
Vertebral Column,— The forty-nine vertebra composing the column are arranged as follows : C 7, D 13 or 14, L (5 or 5, 8 5, C 18. The atlas is wide, and the axis is the only cervical vertebra with a distinct spinous process.
The clavicles are large, the sternum is narrow and the scapula is long and narrow. The humerus is large and has an epicondylar foramen. And the carpus possesses an os centrale: the unciform bone is large.
The pelvis is long and narrow, and the symphysis is limited to the pubis. The tibia and fibula are fused distally, and the OS calcis and scaphoid are very long.
Muscular System.-The panniculus and platysma myoides are as in the Lemurs, but no sphincter colli is